Airtight mail slot



March 9, 1948. P. T. GABLE ET AL 2,437,319

AIR TIGHT MAIL SLOT Filed May 18, 1945 I 2 Sheets-Sheet 2 & 7 //0 '74 S l/ v U 34. i re; 5 I :g ,60

9 2i KIM aa- Z INVENTORS P aa Z .TGabZe l/z/Zzam (TA/e zss ATTDRN EYS Patented Mar. 9, 1948 AIRTIGH'I' MAIL SLOT Paul T. Gable, Harrisburg, and William C. Weiss,

Penbrook, Pa.

Application May 18, 1945, Serial No. 594,518

This invention relates to mail slots and more particularly to that type of mail slot that is airtight and its object is to prevent 'a cold draught of air from passing through the slot.

With the above and other objects in view, the

invention consists in the novel features of construction, combination and arrangement of parts to be hereinafter more fully described, claimed and illustrated in the accompanying drawings in which- Figurel is a front-view of'the front plate of an embodiment of the invention;

Figure 2 is a rear view of the same;

Figure 3 is a rear view of the rear plate of an embodiment of the invention partly broken away; 7 e 1 Figure 4 is a sectional view of Figural;

Figure 5 is a view on the line 4-4 with the airtight door in slightly open position.

Referring now more in detail to the drawings wherein similar characters of reference indicate alon the line 4 4 corresponding parts in the several views, l6 indicates the front of a door D to which the rectangular front plate l2 of an embodiment of the inventionis afilxed by means of screws l4,

The plate I 2 is bevelled on the edges in the usual manner and is provided with the lon tudinally extending mail slot [6, which is positioned on the front in of the door D in alignment with the usual slot S cut entirely through the door D through which the mail is inserted from the front of the door to the rear thereof.

The rear of the plate I2 is provided with the usual elliptical shaped door l8 which covers the interior of the slot l6 and is hingedly mounted thereon by means of a pin 28.

Positioned at approximately the medial point of the rear of the door I8 is a U-shaped bracket 22 having apertures 24 therein to slidably receive 7 a vertical internally threaded sleeve 26.

The sleeve 26 is adapted to receive therein a complementary threaded pin 28 having a locking nut 86 threaded thereon.

The top of the sleeve 26 is notched at opposite points 32 to receive the end 34 of a coil spring 36.

The end 34 of the spring 36 lies at right angles to the, top of the sleeve 26 and is provided with a substantially V-shaped tension portion which is formed by bending a side 38 of the portion downward from the end 34 at 46 at an angle thereto and upward at 42 so that the side 44 lies parallel with the sleeve 26.

The side 44 then continues upward to the spring 36 which is mounted on the pin 26. The

4 Claims. (01. 232-45) opposite end 46 of the coil spring 36 is bent at right angles thereto and bears against the plate l2. The pressure of the spring 86 exerts a downward pressure on the sleeve 26 thereby maintaining contact at all times between the lower end of the pin 28 and a bronze sheet metal plate 48. The spring 86 thereby has a triple function to exert pressure on the door Hi 'to keep it in closed position, to apply pressure on the sleeve 26 to keep the pin in contact with plate 48, and to cause the pin 28 and sleeve 26 to be extended beyond the lower end of the bracket 24 for a purpose to be later described.

The plate 48 extends transversely of the slot S and is provided with downwardly depending portions 56 which are affixed to the front and rear of the door D by any well known fastening means. a

Positioned on the rear 52 of the door D in such a manner that it is in alignment with the slot S of the door D is the air-tight mail slot closure mounting 64.

The closure mounting 54 comprises front and rear plates 56 and 58 having longitudinally ex tending mail slots 60 and 66 therein which as has been stated are in alignment with the slot S.

Between the plates 56 and 58 is a U-shaped plate 62 having the air-tight sealing door 64 slidably mounted therein for vertical movement thereof.

The plates 56, 68 and 62 have aligned openings 65 by which the plates are affixed to the rear 52 of the door D by means oi screws 66.

The door 64 has afiixed thereto by welding or other well known means a lift 68.

The lift 66 comprises a base 10 and an upturned lip 12 at an angle thereto.

The lift 68 is positioned centrally of the lower edge 14 of the door 64 in alignment with the pin 28. I

As the postman inserts mail through the slot iii of the plate l2, the door 18 is pushed inward. As the door 48 describes its arc, the pin 28 slides over the plate 48 and by means of the pressure placed thereon by the spring 36, the pin 26 and the sleeve 26 project beyond the lower edge of the door l8.

As the door l8 continues to open, the pin 28 contacts the lip 12 of the lift 68, this action causing the air-tight door 64 toi'be raised in order that the mail may be passed through slots 66 and 68 into the interior of the house.

As the door 64 is raised upward, the base 18 of the lift 68 is received in a recess 16 positioned in the plate 56 in alignment with the base 16 and 3 the pin and sleeve are thrust inwardly of the bracket 24". Thus the door 64 can be opened or raised to completely uncover the slots 60 and 60'.

When the mail has been deposited and the door 18 has started to assume its closed position, the air-tight door 64 will close by gravity and the mail slot is sealed from air currents attempting to The plate 148 is provided to prevent any undue friction between the pin 28 and the bottom of the slot S.

The threading on the pin and sleeve are pro-- I vided to adjust the pin to doors of varying thicknesses and the lock nut 30 *holds the pin in adjusted position relative to the sleeve.

It will be understood, thereiore by those Skilled in the art, that the embodiment of the invention herein disclosed accomplishes the object of the invention. It also has uses and advantages other than those hereintna slar v ef rre to; also invention and since the embodiment disc qsed herein being only illustrative of the device, the invention is not etopiloeunderstood ,as' restricted thereto since this may be modified --wi' thin the scope of the, rppended claims without departing from the spirit and scope of iihe-invention.

Having thus described-the invention, what is claimed asnew andrdesiredwto: be secured by'Let, ters-Batent is:

1. A device of the character described, comprisinga front plate, a door pivotally' mounted on said plate, a sliding door relatively spaced from said front-plate, a pin on said door adapted to co-act with means on said sliding door whereby said sliding door is raised during the inwardly swinging movement-ofisaidfirstdoor.

upwardly sliding door forming'part of said closure, means on the inner side of said sliding door located in the path of movement of said pin wherebysaid sliding door is raised upward during the inwardly swinging movement of said mail receiving-door.

'3. The invention as in claim 2, wherein said REFERENCES CITED The following references are of record in the file of this patent:

UNITED. STATES. PATENTS Name Date Foss: Feb, 24, 1931 Foss Sept; 29,1931

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